Quote from Yet Another Crank :"A terrorist is someone who tries to extort political change by threatening a civilian population with death and destruction.

That's pretty much it."

Terrorize the citizens and let the citizens pressure the government to change.
The only way a government can be terrorized is with threat of expulsion of those in power and only the citizens can do that in today's world. In the past governments could be terrorized with the threat of invasion, expulsion and killing of its leaders but that's pretty much out of the question now. So what's left is to go after the citizens. Terrorize them.
Of coarse negotiation and compromise is the best way to bring about change but it's hard to negotiate with an entity that wants you dead. When wanting you and yours dead is the change the other party desires, it makes negotiations really tuff.